Jack Straw has admitted for the first time that trade and oil deals with Libya played 'a very big part' in the handling of the Lockerbie bomber's case.

The Justice Secretary said trade was a major influence on his decision to include Abdelbaset Al Megrahi in a prisoner transfer agreement with Libya signed two years ago, just as BP was seeking a multi-billion pound deal there.

The admission casts grave doubt on Gordon Brown's claim this week that there had been 'no conspiracy, no cover-up, no double-dealing, no deal on oil'.